1. Field of the Invention
This invention relates to frame structures for buildings, and in particular to such frame structures having double frames.
2. Related Art
It has been proposed to provide mobile or temporary buildings with spaced frames, the spaces between the frames being filled by a fabric panel, or fabric panels. One example of such a building is described in U.S. Pat. No. 4583331, issued Apr. 22nd 1986 (in the name of the present assignees).
The frames are formed by connecting sections together to form arched frames, giving a clear span. For convenience, efficiency and economic reasons, it is preferred that the various sections be standardized, having a common cross-section. The span of a building will depend on the number of sections in each wall portion and the number of sections in each roof portion. However there is a limit to the span which can be provided. While internal supports can be provided, these interfere with the clear space within the building and are therefore to be avoided. The alternative is, therefore, to increase the cross-section of the sections to make them stronger. Thus it is necessary to stock sections of different cross-sections to satisfy different requirements.